/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package org.dom4j.tree;

import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.dom4j.Comment;
import org.dom4j.Document;
import org.dom4j.DocumentType;
import org.dom4j.Element;
import org.dom4j.IllegalAddException;
import org.dom4j.Node;
import org.dom4j.ProcessingInstruction;
import org.dom4j.QName;
import org.dom4j.Text;
import org.dom4j.Visitor;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;

/**
 * <p> <code>AbstractDocument</code> is an abstract base class for tree
 * implementors to use for implementation inheritence. </p>
 * 
 * @author <a href="mailto:jstrachan@apache.org">James Strachan </a>
 * @version $Revision: 1.2 $
 */
public abstract class AbstractDocument extends AbstractBranch implements
   Document
{

   /** The encoding of this document as stated in the XML declaration */
   protected String encoding;

   public AbstractDocument()
   {
   }

   public short getNodeType()
   {
      return DOCUMENT_NODE;
   }

   public String getPath(Element context)
   {
      return "/";
   }

   public String getUniquePath(Element context)
   {
      return "/";
   }

   public Document getDocument()
   {
      return this;
   }

   public String getXMLEncoding()
   {
      return null;
   }

   public String getStringValue()
   {
      Element root = getRootElement();

      return (root != null) ? root.getStringValue() : "";
   }

   public String asXML()
   {
      OutputFormat format = new OutputFormat();
      format.setEncoding(encoding);

      try
      {
         StringWriter out = new StringWriter();
         XMLWriter writer = new XMLWriter(out, format);
         writer.write(this);
         writer.flush();

         return out.toString();
      }
      catch(IOException e)
      {
         throw new RuntimeException("IOException while generating textual "
            + "representation: " + e.getMessage());
      }
   }

   public void write(Writer out) throws IOException
   {
      OutputFormat format = new OutputFormat();
      format.setEncoding(encoding);

      XMLWriter writer = new XMLWriter(out, format);
      writer.write(this);
   }

   /**
    * <p> <code>accept</code> method is the <code>Visitor Pattern</code>
    * method. </p>
    * 
    * @param visitor <code>Visitor</code> is the visitor.
    */
   public void accept(Visitor visitor)
   {
      visitor.visit(this);

      DocumentType docType = getDocType();

      if(docType != null)
      {
         visitor.visit(docType);
      }

      // visit content
      List content = content();

      if(content != null)
      {
         for(Iterator iter = content.iterator(); iter.hasNext();)
         {
            Object object = iter.next();

            if(object instanceof String)
            {
               Text text = getDocumentFactory().createText((String) object);
               visitor.visit(text);
            }
            else
            {
               Node node = (Node) object;
               node.accept(visitor);
            }
         }
      }
   }

   public String toString()
   {
      return super.toString() + " [Document: name " + getName() + "]";
   }

   public void normalize()
   {
      Element element = getRootElement();

      if(element != null)
      {
         element.normalize();
      }
   }

   public Document addComment(String comment)
   {
      Comment node = getDocumentFactory().createComment(comment);
      add(node);

      return this;
   }

   public Document addProcessingInstruction(String target, String data)
   {
      ProcessingInstruction node =
         getDocumentFactory().createProcessingInstruction(target, data);
      add(node);

      return this;
   }

   public Document addProcessingInstruction(String target, Map data)
   {
      ProcessingInstruction node =
         getDocumentFactory().createProcessingInstruction(target, data);
      add(node);

      return this;
   }

   public Element addElement(String name)
   {
      Element element = getDocumentFactory().createElement(name);
      add(element);

      return element;
   }

   public Element addElement(String qualifiedName, String namespaceURI)
   {
      Element element =
         getDocumentFactory().createElement(qualifiedName, namespaceURI);
      add(element);

      return element;
   }

   public Element addElement(QName qName)
   {
      Element element = getDocumentFactory().createElement(qName);
      add(element);

      return element;
   }

   public void setRootElement(Element rootElement)
   {
      clearContent();

      if(rootElement != null)
      {
         super.add(rootElement);
         rootElementAdded(rootElement);
      }
   }

   public void add(Element element)
   {
      checkAddElementAllowed(element);
      super.add(element);
      rootElementAdded(element);
   }

   public boolean remove(Element element)
   {
      boolean answer = super.remove(element);
      Element root = getRootElement();

      if((root != null) && answer)
      {
         setRootElement(null);
      }

      element.setDocument(null);

      return answer;
   }

   public Node asXPathResult(Element parent)
   {
      return this;
   }

   protected void childAdded(Node node)
   {
      if(node != null)
      {
         node.setDocument(this);
      }
   }

   protected void childRemoved(Node node)
   {
      if(node != null)
      {
         node.setDocument(null);
      }
   }

   protected void checkAddElementAllowed(Element element)
   {
      Element root = getRootElement();

      if(root != null)
      {
         throw new IllegalAddException(this, element,
            "Cannot add another element to this "
               + "Document as it already has a root " + "element of: "
               + root.getQualifiedName());
      }
   }

   /**
    * Called to set the root element variable
    * 
    * @param rootElement DOCUMENT ME!
    */
   protected abstract void rootElementAdded(Element rootElement);

   public void setXMLEncoding(String enc)
   {
      this.encoding = enc;
   }
}

/*
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided that the
 * following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and
 * notices. Redistributions must also contain a copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived
 * from this Software without prior written permission of MetaStuff, Ltd. For
 * written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may
 * "DOM4J" appear in their names without prior written permission of MetaStuff,
 * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
